#![doc = self_test!(=>
)]
#[cfg(not(feature = "default"))]
compile_error!(
"The feature `default` must be enabled to ensure \
forward compatibility with future version of this crate"
);
extern crate proc_macro;
use proc_macro::{TokenStream, TokenTree};
use std::borrow::Cow;
use std::collections::HashSet;
use std::convert::TryFrom;
use std::fmt::Write;
use std::path::Path;
use std::str::FromStr;
fn error(e: &str) -> TokenStream {
TokenStream::from_str(&format!("::core::compile_error!{{\"{}\"}}", e.escape_default())).unwrap()
}
fn compile_error(msg: &str, tt: Option<TokenTree>) -> TokenStream {
let span = tt.as_ref().map_or_else(proc_macro::Span::call_site, TokenTree::span);
use proc_macro::{Delimiter, Group, Ident, Literal, Punct, Spacing};
use std::iter::FromIterator;
TokenStream::from_iter(vec![
TokenTree::Ident(Ident::new("compile_error", span)),
TokenTree::Punct({
let mut punct = Punct::new('!', Spacing::Alone);
punct.set_span(span);
punct
}),
TokenTree::Group({
let mut group = Group::new(Delimiter::Brace, {
TokenStream::from_iter([TokenTree::Literal({
let mut string = Literal::string(msg);
string.set_span(span);
string
})])
});
group.set_span(span);
group
}),
])
}
#[derive(Default)]
struct Args {
feature_label: Option<String>,
}
fn parse_args(input: TokenStream) -> Result<Args, TokenStream> {
let mut token_trees = input.into_iter().fuse();
match token_trees.next() {
None => return Ok(Args::default()),
Some(TokenTree::Ident(ident)) if ident.to_string() == "feature_label" => (),
tt => return Err(compile_error("expected `feature_label`", tt)),
}
match token_trees.next() {
Some(TokenTree::Punct(p)) if p.as_char() == '=' => (),
tt => return Err(compile_error("expected `=`", tt)),
}
let feature_label;
if let Some(tt) = token_trees.next() {
match litrs::StringLit::<String>::try_from(&tt) {
Ok(string_lit) if string_lit.value().contains("{feature}") => {
feature_label = string_lit.value().to_string()
}
_ => {
return Err(compile_error(
"expected a string literal containing the substring \"{feature}\"",
Some(tt),
))
}
}
} else {
return Err(compile_error(
"expected a string literal containing the substring \"{feature}\"",
None,
));
}
if let tt @ Some(_) = token_trees.next() {
return Err(compile_error("unexpected token after the format string", tt));
}
Ok(Args { feature_label: Some(feature_label) })
}
#[proc_macro]
pub fn document_features(tokens: TokenStream) -> TokenStream {
parse_args(tokens)
.and_then(|args| document_features_impl(&args))
.unwrap_or_else(std::convert::identity)
}
fn document_features_impl(args: &Args) -> Result<TokenStream, TokenStream> {
let path = std::env::var("CARGO_MANIFEST_DIR").unwrap();
let mut cargo_toml = std::fs::read_to_string(Path::new(&path).join("Cargo.toml"))
.map_err(|e| error(&format!("Can't open Cargo.toml: {:?}", e)))?;
if !has_doc_comments(&cargo_toml) {
if let Ok(orig) = std::fs::read_to_string(Path::new(&path).join("Cargo.toml.orig")) {
if has_doc_comments(&orig) {
cargo_toml = orig;
}
}
}
let result = process_toml(&cargo_toml, args).map_err(|e| error(&e))?;
Ok(std::iter::once(proc_macro::TokenTree::from(proc_macro::Literal::string(&result))).collect())
}
fn has_doc_comments(cargo_toml: &str) -> bool {
let mut lines = cargo_toml.lines().map(str::trim);
while let Some(line) = lines.next() {
if line.starts_with("## ") || line.starts_with("#! ") {
return true;
}
let before_coment = line.split_once('#').map_or(line, |(before, _)| before);
if line.starts_with("#") {
continue;
}
if let Some((_, mut quote)) = before_coment.split_once("\"\"\"") {
loop {
if let Some((_, s)) = quote.split_once('\\') {
quote = s.strip_prefix('\\').or_else(|| s.strip_prefix('"')).unwrap_or(s);
continue;
}
if let Some((_, out_quote)) = quote.split_once("\"\"\"") {
let out_quote = out_quote.trim_start_matches('"');
let out_quote =
out_quote.split_once('#').map_or(out_quote, |(before, _)| before);
if let Some((_, q)) = out_quote.split_once("\"\"\"") {
quote = q;
continue;
}
break;
};
match lines.next() {
Some(l) => quote = l,
None => return false,
}
}
}
}
false
}
#[test]
fn test_has_doc_coment() {
assert!(has_doc_comments("foo\nbar\n## comment\nddd"));
assert!(!has_doc_comments("foo\nbar\n#comment\nddd"));
assert!(!has_doc_comments(
r#"
[[package.metadata.release.pre-release-replacements]]
exactly = 1 # not a doc comment
file = "CHANGELOG.md"
replace = """
<!-- next-header -->
## [Unreleased] - ReleaseDate
"""
search = "<!-- next-header -->"
array = ["""foo""", """
bar""", """eee
## not a comment
"""]
"#
));
assert!(has_doc_comments(
r#"
[[package.metadata.release.pre-release-replacements]]
exactly = 1 # """
file = "CHANGELOG.md"
replace = """
<!-- next-header -->
## [Unreleased] - ReleaseDate
"""
search = "<!-- next-header -->"
array = ["""foo""", """
bar""", """eee
## not a comment
"""]
## This is a comment
feature = "45"
"#
));
assert!(!has_doc_comments(
r#"
[[package.metadata.release.pre-release-replacements]]
value = """" string \"""
## within the string
\""""
another_string = """"" # """
## also within"""
"#
));
assert!(has_doc_comments(
r#"
[[package.metadata.release.pre-release-replacements]]
value = """" string \"""
## within the string
\""""
another_string = """"" # """
## also within"""
## out of the string
foo = bar
"#
));
}
fn process_toml(cargo_toml: &str, args: &Args) -> Result<String, String> {
let mut lines = cargo_toml
.lines()
.map(str::trim)
.filter(|l| {
!l.is_empty() && (!l.starts_with('#') || l.starts_with("##") || l.starts_with("#!"))
});
let mut top_comment = String::new();
let mut current_comment = String::new();
let mut features = vec![];
let mut default_features = HashSet::new();
let mut current_table = "";
while let Some(line) = lines.next() {
if let Some(x) = line.strip_prefix("#!") {
if !x.is_empty() && !x.starts_with(' ') {
continue; }
if !current_comment.is_empty() {
return Err("Cannot mix ## and #! comments between features.".into());
}
if top_comment.is_empty() && !features.is_empty() {
top_comment = "\n".into();
}
writeln!(top_comment, "{}", x).unwrap();
} else if let Some(x) = line.strip_prefix("##") {
if !x.is_empty() && !x.starts_with(' ') {
continue; }
writeln!(current_comment, " {}", x).unwrap();
} else if let Some(table) = line.strip_prefix('[') {
current_table = table
.split_once(']')
.map(|(t, _)| t.trim())
.ok_or_else(|| format!("Parse error while parsing line: {}", line))?;
if !current_comment.is_empty() {
let dep = current_table
.rsplit_once('.')
.and_then(|(table, dep)| table.trim().ends_with("dependencies").then(|| dep))
.ok_or_else(|| format!("Not a feature: `{}`", line))?;
features.push((
dep.trim(),
std::mem::take(&mut top_comment),
std::mem::take(&mut current_comment),
));
}
} else if let Some((dep, rest)) = line.split_once('=') {
let dep = dep.trim().trim_matches('"');
let rest = get_balanced(rest, &mut lines)
.map_err(|e| format!("Parse error while parsing value {}: {}", dep, e))?;
if current_table == "features" && dep == "default" {
let defaults = rest
.trim()
.strip_prefix('[')
.and_then(|r| r.strip_suffix(']'))
.ok_or_else(|| format!("Parse error while parsing dependency {}", dep))?
.split(',')
.map(|d| d.trim().trim_matches(|c| c == '"' || c == '\'').trim().to_string())
.filter(|d| !d.is_empty());
default_features.extend(defaults);
}
if !current_comment.is_empty() {
if current_table.ends_with("dependencies") {
if !rest
.split_once("optional")
.and_then(|(_, r)| r.trim().strip_prefix('='))
.map_or(false, |r| r.trim().starts_with("true"))
{
return Err(format!("Dependency {} is not an optional dependency", dep));
}
} else if current_table != "features" {
return Err(format!(
r#"Comment cannot be associated with a feature: "{}""#,
current_comment.trim()
));
}
features.push((
dep,
std::mem::take(&mut top_comment),
std::mem::take(&mut current_comment),
));
}
}
}
if !current_comment.is_empty() {
return Err("Found comment not associated with a feature".into());
}
if features.is_empty() {
return Ok("*No documented features in Cargo.toml*".into());
}
let mut result = String::new();
for (f, top, comment) in features {
let default = if default_features.contains(f) { " *(enabled by default)*" } else { "" };
if !comment.trim().is_empty() {
if let Some(feature_label) = &args.feature_label {
writeln!(
result,
"{}* {}{} —{}",
top,
feature_label.replace("{feature}", f),
default,
comment.trim_end(),
)
.unwrap();
} else {
writeln!(result, "{}* **`{}`**{} —{}", top, f, default, comment.trim_end())
.unwrap();
}
} else if let Some(feature_label) = &args.feature_label {
writeln!(result, "{}* {}{}", top, feature_label.replace("{feature}", f), default,)
.unwrap();
} else {
writeln!(result, "{}* **`{}`**{}", top, f, default).unwrap();
}
}
result += &top_comment;
Ok(result)
}
fn get_balanced<'a>(
first_line: &'a str,
lines: &mut impl Iterator<Item = &'a str>,
) -> Result<Cow<'a, str>, String> {
let mut line = first_line;
let mut result = Cow::from("");
let mut in_quote = false;
let mut level = 0;
loop {
let mut last_slash = false;
for (idx, b) in line.as_bytes().iter().enumerate() {
if last_slash {
last_slash = false
} else if in_quote {
match b {
b'\\' => last_slash = true,
b'"' | b'\'' => in_quote = false,
_ => (),
}
} else {
match b {
b'\\' => last_slash = true,
b'"' => in_quote = true,
b'{' | b'[' => level += 1,
b'}' | b']' if level == 0 => return Err("unbalanced source".into()),
b'}' | b']' => level -= 1,
b'#' => {
line = &line[..idx];
break;
}
_ => (),
}
}
}
if result.len() == 0 {
result = Cow::from(line);
} else {
*result.to_mut() += line;
}
if level == 0 {
return Ok(result);
}
line = if let Some(l) = lines.next() {
l
} else {
return Err("unbalanced source".into());
};
}
}
#[test]
fn test_get_balanced() {
assert_eq!(
get_balanced(
"{",
&mut IntoIterator::into_iter(["a", "{ abc[], #ignore", " def }", "}", "xxx"])
),
Ok("{a{ abc[], def }}".into())
);
assert_eq!(
get_balanced("{ foo = \"{#\" } #ignore", &mut IntoIterator::into_iter(["xxx"])),
Ok("{ foo = \"{#\" } ".into())
);
assert_eq!(
get_balanced("]", &mut IntoIterator::into_iter(["["])),
Err("unbalanced source".into())
);
}
#[cfg(feature = "self-test")]
#[proc_macro]
#[doc(hidden)]
pub fn self_test_helper(input: TokenStream) -> TokenStream {
let mut code = String::new();
for line in (&input).to_string().trim_matches(|c| c == '"' || c == '#').lines() {
if line.strip_prefix('#').map_or(false, |x| x.is_empty() || x.starts_with(' ')) {
code += "#";
}
code += line;
code += "\n";
}
process_toml(&code, &Args::default()).map_or_else(
|e| error(&e),
|r| std::iter::once(proc_macro::TokenTree::from(proc_macro::Literal::string(&r))).collect(),
)
}
#[cfg(feature = "self-test")]
macro_rules! self_test {
(#[doc = $toml:literal] => #[doc = $md:literal]) => {
concat!(
"\n`````rust\n\
fn normalize_md(md : &str) -> String {
md.lines().skip_while(|l| l.is_empty()).map(|l| l.trim())
.collect::<Vec<_>>().join(\"\\n\")
}
assert_eq!(normalize_md(document_features::self_test_helper!(",
stringify!($toml),
")), normalize_md(",
stringify!($md),
"));\n`````\n\n"
)
};
}
#[cfg(not(feature = "self-test"))]
macro_rules! self_test {
(#[doc = $toml:literal] => #[doc = $md:literal]) => {
concat!(
"This contents in Cargo.toml:\n`````toml",
$toml,
"\n`````\n Generates the following:\n\
<table><tr><th>Preview</th></tr><tr><td>\n\n",
$md,
"\n</td></tr></table>\n\n \n",
)
};
}
use self_test;
#[cfg(doc)]
struct FeatureLabelCompilationTest;
#[cfg(test)]
mod tests {
use super::{process_toml, Args};
#[track_caller]
fn test_error(toml: &str, expected: &str) {
let err = process_toml(toml, &Args::default()).unwrap_err();
assert!(err.contains(expected), "{:?} does not contain {:?}", err, expected)
}
#[test]
fn only_get_balanced_in_correct_table() {
process_toml(
r#"
[package.metadata.release]
pre-release-replacements = [
{test=\"\#\# \"},
]
[abcd]
[features]#xyz
#! abc
#
###
#! def
#!
## 123
## 456
feat1 = ["plop"]
#! ghi
no_doc = []
##
feat2 = ["momo"]
#! klm
default = ["feat1", "something_else"]
#! end
"#,
&Args::default(),
)
.unwrap();
}
#[test]
fn no_features() {
let r = process_toml(
r#"
[features]
[dependencies]
foo = 4;
"#,
&Args::default(),
)
.unwrap();
assert_eq!(r, "*No documented features in Cargo.toml*");
}
#[test]
fn no_features2() {
let r = process_toml(
r#"
[packages]
[dependencies]
"#,
&Args::default(),
)
.unwrap();
assert_eq!(r, "*No documented features in Cargo.toml*");
}
#[test]
fn parse_error3() {
test_error(
r#"
[features]
ff = []
[abcd
efgh
[dependencies]
"#,
"Parse error while parsing line: [abcd",
);
}
#[test]
fn parse_error4() {
test_error(
r#"
[features]
## dd
## ff
#! ee
## ff
"#,
"Cannot mix",
);
}
#[test]
fn parse_error5() {
test_error(
r#"
[features]
## dd
"#,
"not associated with a feature",
);
}
#[test]
fn parse_error6() {
test_error(
r#"
[features]
# ff
foo = []
default = [
#ffff
# ff
"#,
"Parse error while parsing value default",
);
}
#[test]
fn parse_error7() {
test_error(
r#"
[features]
# f
foo = [ x = { ]
bar = []
"#,
"Parse error while parsing value foo",
);
}
#[test]
fn not_a_feature1() {
test_error(
r#"
## hallo
[features]
"#,
"Not a feature: `[features]`",
);
}
#[test]
fn not_a_feature2() {
test_error(
r#"
[package]
## hallo
foo = []
"#,
"Comment cannot be associated with a feature: \"hallo\"",
);
}
#[test]
fn non_optional_dep1() {
test_error(
r#"
[dev-dependencies]
## Not optional
foo = { version = "1.2", optional = false }
"#,
"Dependency foo is not an optional dependency",
);
}
#[test]
fn non_optional_dep2() {
test_error(
r#"
[dev-dependencies]
## Not optional
foo = { version = "1.2" }
"#,
"Dependency foo is not an optional dependency",
);
}
#[test]
fn basic() {
let toml = r#"
[abcd]
[features]#xyz
#! abc
#
###
#! def
#!
## 123
## 456
feat1 = ["plop"]
#! ghi
no_doc = []
##
feat2 = ["momo"]
#! klm
default = ["feat1", "something_else"]
#! end
"#;
let parsed = process_toml(toml, &Args::default()).unwrap();
assert_eq!(
parsed,
" abc\n def\n\n* **`feat1`** *(enabled by default)* — 123\n 456\n\n ghi\n* **`feat2`**\n\n klm\n end\n"
);
let parsed = process_toml(
toml,
&Args {
feature_label: Some(
"<span class=\"stab portability\"><code>{feature}</code></span>".into(),
),
},
)
.unwrap();
assert_eq!(
parsed,
" abc\n def\n\n* <span class=\"stab portability\"><code>feat1</code></span> *(enabled by default)* — 123\n 456\n\n ghi\n* <span class=\"stab portability\"><code>feat2</code></span>\n\n klm\n end\n"
);
}
#[test]
fn dependencies() {
let toml = r#"
#! top
[dev-dependencies] #yo
## dep1
dep1 = { version="1.2", optional=true}
#! yo
dep2 = "1.3"
## dep3
[target.'cfg(unix)'.build-dependencies.dep3]
version = "42"
optional = true
"#;
let parsed = process_toml(toml, &Args::default()).unwrap();
assert_eq!(parsed, " top\n* **`dep1`** — dep1\n\n yo\n* **`dep3`** — dep3\n");
let parsed = process_toml(
toml,
&Args {
feature_label: Some(
"<span class=\"stab portability\"><code>{feature}</code></span>".into(),
),
},
)
.unwrap();
assert_eq!(parsed, " top\n* <span class=\"stab portability\"><code>dep1</code></span> — dep1\n\n yo\n* <span class=\"stab portability\"><code>dep3</code></span> — dep3\n");
}
#[test]
fn multi_lines() {
let toml = r#"
[package.metadata.foo]
ixyz = [
["array"],
[
"of",
"arrays"
]
]
[dev-dependencies]
## dep1
dep1 = {
version="1.2-}",
optional=true
}
[features]
default = [
"goo",
"\"]",
"bar",
]
## foo
foo = [
"bar"
]
## bar
bar = [
]
"#;
let parsed = process_toml(toml, &Args::default()).unwrap();
assert_eq!(
parsed,
"* **`dep1`** — dep1\n* **`foo`** — foo\n* **`bar`** *(enabled by default)* — bar\n"
);
let parsed = process_toml(
toml,
&Args {
feature_label: Some(
"<span class=\"stab portability\"><code>{feature}</code></span>".into(),
),
},
)
.unwrap();
assert_eq!(
parsed,
"* <span class=\"stab portability\"><code>dep1</code></span> — dep1\n* <span class=\"stab portability\"><code>foo</code></span> — foo\n* <span class=\"stab portability\"><code>bar</code></span> *(enabled by default)* — bar\n"
);
}
#[test]
fn dots_in_feature() {
let toml = r#"
[features]
## This is a test
"teßt." = []
default = ["teßt."]
[dependencies]
## A dep
"dep" = { version = "123", optional = true }
"#;
let parsed = process_toml(toml, &Args::default()).unwrap();
assert_eq!(
parsed,
"* **`teßt.`** *(enabled by default)* — This is a test\n* **`dep`** — A dep\n"
);
let parsed = process_toml(
toml,
&Args {
feature_label: Some(
"<span class=\"stab portability\"><code>{feature}</code></span>".into(),
),
},
)
.unwrap();
assert_eq!(
parsed,
"* <span class=\"stab portability\"><code>teßt.</code></span> *(enabled by default)* — This is a test\n* <span class=\"stab portability\"><code>dep</code></span> — A dep\n"
);
}
}